Δεν ξέρω πού να βάλω αυτό το έπιπλο.

Δεν is the normal negation word for not before a verb in Modern Greek.

So:

• ξέρω = I know
• δεν ξέρω = I don’t know

It usually comes directly before the verb phrase it negates.

Greek often leaves subject pronouns out because the verb ending already tells you who the subject is.

Here:

• ξέρω = I know
• βάλω = I put / I place in this form

So Greek does not need an explicit εγώ (I) unless you want emphasis:

• Εγώ δεν ξέρω... = I don’t know... / As for me, I don’t know...

Πού means where.

In this sentence, it introduces an indirect question:

• Δεν ξέρω πού... = I don’t know where...

So this is not a direct question like Πού είναι; (Where is it?), but an embedded one: I don’t know where...

This is mainly a spelling issue.

Greek normally does not accent most one-syllable words, but πού is one of the exceptions. The accent helps distinguish it from που, which often functions as a relative word meaning that/which/where depending on context.

So:

• πού = where?
• που = usually that / which / where in a relative-clause sense

Because Greek uses να + verb where English often uses an infinitive such as to put.

English says:

• I don’t know where to put it

Greek does not have a normal everyday infinitive for this, so it says:

• Δεν ξέρω πού να βάλω...

Here να introduces the verb form needed after πού in this kind of structure.

Να does not have one single neat English equivalent. In different contexts it can correspond to things like to, that, should, or a subjunctive idea.

In this sentence, the easiest way to understand it is:

• πού να βάλω = where to put

So να is part of the standard Greek way of expressing this idea. It is not literally the same as English to, but that is often the closest natural translation here.

Because βάλω is the perfective/aorist form used here for a single, complete action: placing this one item somewhere.

• βάζω = I put / I am putting / I put regularly
• βάλω = I put, in the sense of place it once / complete the action

Since the sentence is about finding a place for one piece of furniture, Greek naturally uses να βάλω.

If you said να βάζω, it would sound more like:

• where I should keep putting it
• where I usually put it
• where to be putting it repeatedly

That is not the intended meaning here.

No. By itself here, βάλω is not future tense. It is the form used after να.

Compare:

• να βάλω = to put / that I put / should put depending on context
• θα βάλω = I will put

So in this sentence, βάλω is not I will put. The future meaning would need θα.

Yes, and it is grammatical, but the nuance is a little different.

• Δεν ξέρω πού να βάλω αυτό το έπιπλο = I don’t know where to put this piece of furniture
• Δεν ξέρω πού θα βάλω αυτό το έπιπλο = I don’t know where I will put this piece of furniture

The να version sounds more like a problem of choice or placement: What spot should I choose?

The θα version sounds more directly future-oriented: I don’t know where I’m going to put it.

In many situations, both are possible.

Because that is the normal Greek pattern with demonstratives:

• αυτό το έπιπλο = this piece of furniture
• literally something like this the furniture-piece

Unlike English, Greek usually keeps the definite article after the demonstrative when a noun follows it.

So:

• αυτό alone = this / this one
• αυτό το έπιπλο = this piece of furniture

Because έπιπλο is a neuter singular noun.

In Greek, articles and demonstratives must agree with the noun in gender, number, and case.

So here:

• αυτό = neuter singular
• το = neuter singular article
• έπιπλο = neuter singular noun

Also, this phrase is the object of βάλω, so it is in the accusative, but for many neuter nouns the nominative and accusative forms look the same.

In the singular, έπιπλο usually means a piece of furniture.

So in this sentence, a very natural understanding is:

• this piece of furniture

The plural is:

• έπιπλα = furniture items / pieces of furniture

English uses furniture as an uncountable noun, but Greek often uses countable forms more directly.

Because Greek, like English, puts the question word at the start of the embedded question.

So:

• πού να βάλω = where to put

That order is the normal one. You would not usually move πού later in the clause.

A rough pronunciation is:

then KSE-ro POO na VA-lo af-TO to E-pee-plo

More precisely:

[ðen ˈksero pu na ˈvalo afˈto to ˈepiplo]

A few useful sound notes:

• δ in δεν sounds like th in this
• ξ sounds like ks
• β in Modern Greek sounds like v, not English b
• ού in πού sounds like oo in food
• stress falls on:
  • ξέρω
  • πού
  • βάλω
  • αυτό
  • έπιπλο